Fertilization with Silicon in Garlic Grown at Low and High Altitudes in a Semi-arid Region.

Objective: To evaluate the effect of Si fertilization on the growth and yield of common garlic under semi-arid cultivation conditions. Methods: Two field experiments were conducted simultaneously in Mossoró and São Miguel, Rio Grande do Norte, Brazil. The experiment was arranged in a randomized block design, in a 2 × 5 factorial scheme, with two sources of Si (calcium and potassium silicate) and five doses (0, 2, 4, 6, and 8 kg ha⁻¹) applied via foliar. Results: Applying Si doses promoted increased height, dry mass, and yield of common garlic in Mossoró and São Miguel. The effect of Si doses on garlic was independent of the sources used since there was no significant effect for this factor on all variables. In Mossoró, the plants reached maximum height (51.38 cm) at the dose of 4.6 kg ha⁻¹ of Si, higher accumulation of leaf dry matter (3.84 g per plant), bulb (4.53 g per plant) and total (8.37 g per plant) with 4 kg ha⁻¹ of Si and higher commercial (2.72 t ha⁻¹) and total (3.95 t ha⁻¹) yield of bulbs at the doses of 4.1 and 4.4 kg ha⁻¹ of Si, respectively. In São Miguel, the plants reached the highest height (57.09 cm) and total dry matter accumulation (9.74 g per plant) with 2.9 kg ha⁻¹ of Si, maximum accumulation of bulb dry matter (7.10 g per plant) with 2.6 kg ha⁻¹ of Si and higher values of commercial (6.62 t ha⁻¹) and total (6.64 t ha⁻¹) productivity applying 3.5 and 3.9 kg ha⁻¹ of Si, respectively. Conclusions: The foliar application of Si improves the growth and yield characteristics of common garlic bulbs grown in a semi-arid region. Using different sources of Si does not influence the growth and yield of common garlic. [ABSTRACT FROM AUTHOR]